Photography



Patented June 6, 1944 PHOTOGRAPHY Clayton F. A. White, Stelton, N. J.,assgnor, by mesne assignments, to E. I. du Pont'de Nemours & Company,`Wilmington, Del., a. corporation of Delaware Application August 1,1940, Serial No. 349,228

` 6 claims.: (ci. :a5- 2) At the present time there are a great manytypes of processes of color photography wherein colored images areformed. They are quite diverse in character. Some require a l'argenumber of processing steps which is uneconomical, require excessiveprocessing treatment, and do not result in sharp, true color images.

Many promising processes for producing colored images involve the use ofrcolor formers or dye intermediates which form azomethine orqulnoneimine dyestuffs upon development of exposed or latent silverimages with primary aromatic amino developing agents. The colorformersare incorporated in light sensitive emulsion layers which in the case of3-color photog raphy, are so arranged and sensitized that each layerwill record about one third of the visible spectrum. In other relatedprocesses the light sensitive emulsions are .mixed and the color formersare absorbed on the silver halide grains.

The just described elements and processes have a number of disadvantagesin that many color formers (l) reduce the overall sensitivity ofemulsions, (2) reduce or destroy the color sensitized characteristics ofemulsions, (3) produce general emulsion fog. This is particularly trueof the insoluble Ahigh molecular weight imu mobile or non-migratory typewhich are incorporated in emulsion layers. Others wander in emulsionlayers and cause dilution of color.

which can be successfully processed to colored images by a minimumnumber of processing nlm which can be processed without excess handlingthereof.

A further object is to provide novelrnethods of developing or formingcolored images in multilayer lms. A further object is to provide areversal process for producing color images in an exposed multilayerelement involving a few simple steps. Another object is to provide aprocess for simultaneously producing colored images in unsensitizedlayers in a photographic element. Still other objects will appearhereinafter.

The above objects are accomplished and the mentioned disadvantagesovercome by the hereinafter described invention which in its broaderaspects comprises the production and use of photographic elementscomprising reducible silver salt, generally a silver halide, coating orlayer and at least one co-acting strata or layer which may be in contacttherewith or spaced therefrom, comprising an immobile dye intermediateor color former capable of forming a quinoneimine dye e. g. anindophenol, indoanisteps. Another object is to prov'ide a multilayer 55lineor an azomethine dye upon color forming development and an azo dyeas the reverse image upon appropriate treatment.

Suitable elements comprise a base and at least two co-acting layers, oneof which comprises a reducible silver salt and the other of whichcomprises an immobile dye intermediate or color former. The immobile dyeintermediate or color former layer may be of two general types: (l)composed of an immobile dye intermediate or color former uniformlydistributed or dispersed in a water permeable binding or supportingagent, and (2) composed of a fllm forming material containing within itsstructure dye forming nuclei, i. e. nuclei capable of forming anindophenol, indoaniline or azomethine dye and also an azo dye uponappropriate treatment. In this embodiment the dye intermediate colorformer itself constitutes a layer or strata of the It will be obviousfrom the general considerations above that the invention is ofconsiderable scope and not limited to one or two specific types ofphotographic elements or processes. 0n the contrary, it` embodies manyaspects and many modications can be made. In all such elements, however,the immobile dye intermediate or color former layers or strata areseparate from their co-acting reducible silver salt layers but do nothave any water impermeable layers or membranes therebetween. The dyeintermediate or color former layer or layers andcoacting silver saltlayer constitutes a color yielding unit., A plurality of color units areused in.

the elements herein described which are useful for multicolorphotography.

In one embodiment of the invention the dye intermediate or color formerlayers are immediately adjacent the silver salt layers. One or morecolor former or dye intermediate layers may co-act with a single silversalt layer and constitute a single color yielding unit. Thus, colorformer layers may be placed on each side of the silver salt layer. Thecolor formers may yield dyes of identical color or dierent colors whichform a composite dye image of the proper color. For instance, onepredominately blue and the other predominately green may be used ior theblue-green unit.

In another embodiment of the invention the color-former layers areseparated from respective co-acting reducible silver salt layers by alight transparent strata or layer composed o1 a substantially waterinsoluble, water permeable material or colloid. Suitable materials arecellulose derivatives, e. g. lower alkylethers, esters, glycollates,etc., regenerated cellulose, gelatin, agaragar, etc.

The more complex ramifications of the invention will be more readilyunderstood by the following description of the preparation and colorprocessing of a simple two layer film element. A cellulose acetate nlmbase is coated with a gelatino-silver bromide emulsion to form a thincoating or layer. A thin coating of the resinous color former such assalicylaldehyde acetal of polyvinyl alcohol is superimposed over theemulsion layer. The iilm element is exposed to record an object image,then developed with a color forming developing agent, for example, in adeveloper solution containing a primary aromatic amino developing agent,whereupon a silver image is formed in the original silver halide strataor layer and a colored image of an indophenol dye is formed in thecontiguous color formervor dye intermediate layer. Upon removal of thesilver image the dye image remains solely in the contiguous layer.

A similar element may be processed to form a reverse dye image by iirstdeveloping the exposed lm in an ordinary or non-color forming developer.Then, the reverse image is developed with color-forming developingagent. Re-exposure, either chemical or physical, may be resorted to ifdesired prior to the "second development. However, it is oftenadvantageous to use an energetic dye forming reducing bath containing anorganic nitrogeneous base having an association exponent of at least 9.0and a primary amino developing agent. Suitable baths of this type aredisclosed inMeschter application, Serial No. 295,685.

For multicolor photography. the elements may comprise a plurality ofcolor yielding component units embodied in a single element which are soarranged and/or sensitive that each unit will produce a dye having acolor corresponding to a diierent portion of the color spectrum. Eachcolor component unit comprises a reducible silver salt layer or strataand at least one co-acting strata or layer in contact therewithcontaining at least one immobile dye intermediate capable of forming anlndophenoL, indoaniline or azomethine dye and also an azo dye therein.

In some modifications, each or one or more or the color component unitsmay comprise two or more color yielding layers or strata which arepreferably disposed on opposite sides of the reducible silver saltlayer. The immobile dye intermediates or color iormers in the layers arechosen so that together they form or each forms a composite dye imagewhich is related in its color to the utilized sensitivity of thereducible silver salt layer in said unit. For color forming developmentprocesses the color farmers or former form an indophenol, indoaniline orazomethine dye or composite dye image which is related in color to theutilized sensitivity of the respective unit. For azo reversal processesthe color former or color formers are chosen so that they form an azodye image or composite dye image which is related in color to theutilized sensitivity of the respective unit.

In the case of elements which are to be used in reversal processes ofphotography, the color former or color formers are chosen so that theyform a dye image or composite dye image which is complementary in colorto the utilized sensitivity of its respective unit. The color fol-mersfor use in color development reversal processes should be chosen so thatthey form indophenol, indoaniline or azomethine dyes complementary incolor to the utilized sensitivity of the respective units. Similarly,for azo reversal processes, the color formers or dye intermediatesshould be chosen so that they form an azo dye or composite azo dye imagewhich is complementary in color to the utilized sensitivity of therespective units.

Film elements useful as print stocks for color processes which do nothave to meet all the requirements for the reproduction of a naturalcolor scene by reversal methods. the color formera need not yield colorscomplementary to the utilized sensitivity of respective umts. Thearrangement of the units, type of scene or image to be reproduced, etc.have a deiinite bearing upon the choice of dyestu component.

When two or more color yielding component units are used, it is oftendesirable that they be separated by an non-reactive layer, lm base. Apractical two-color element, for instance, has the transparent baseseparating the sensitive layers and the co-acting color former layersare contiguous thereto. That is, at least one color yielding componentunit is placed on each side of the base. Various modiiications instructure may be made, but it is preferred that the light sensitivelayers be innermost. In another practical element the two color yieldingunits are placed on the same side of the base. The base may be tintedand/or contain an antihalation strata or layer.

A practical 3-color element has two light sensitive layers with thecontiguous co-acting color former layers or two color yielding componentunits separated by the transparent base. A third light sensitive layeris separated from the nearest emulsion layer by at least two layers.These may, of course, be the two respective color former layers. In amodified construction, a least one additional Water permeable layer orstrata separates the last-described two emulsion layers. In anotherpractical 3color element three color yielding units are placed on oneside of the base. 'I'he base may be tinted and/or contain anantihalation strata or layer.

The color yielding units may contain various other photographicmaterials or strata. Thus, they may contain light ltering materials suchas dyes or pigments or colloidal metals, e. g. colloidal silver, thatis, silver in such a state that the single particles cannot be discernedwith the aid or a microscope; which absorb certain wave lengths ofgenerally the light. These materials may constitute separate layers orstrata or they may beincorporated in the color former or dyeintermediate layers or strata or in the light sensitive or silver saltlayers or strata.

In many types of film elementsifor use in multicolor photography, it isdesirable that a yellow screening dye be placed before the red and greenrecording layers so that they will not be exposed to the blue region ofthe spectrum, e. g. blue, violet and ultra violet. Suitable yellowscreening materials include Tartrazine, Luxol Yellow, Naphthol Yellow,Auramine, cadmium sulde, etc.

In lm elements for multicolor photography it often is desirable to usered colored filtering materials (i. e. blue-green light absorbing) whichare placed before the red recording layers. This obviates the necessityfor green-blind sensitizing dyes. Suitable materials of this typeinclude Congo red (C. I. 370), Carmosln M, uranine (C. I.

former layers, light sensitive `or reducible silver salt layers andintermediate layers may vary over a wi'de range.A The thickness used, ofcourse, depends on many factors including the nature of the particularcolor former chosen, the Water permeable binding or supporting agent ormedium, the

type of light sensitive silver salt and binding medium therefor, and-the purpose for which the element is to be used. A

A practical range of thicknesses for the dye intermediate or colorformer layer and/or composite wherein a water permeable binder orsupporting agent is used may Vary from about 1.5;; to about 5.0M. Apreferred range is about 2.0 to 4.0m In general a thicker layer isrequired for a print stock than for a reversal stock. A practical rangeof thicknesses for the emulsion or reducible silver salt layers may varyfrom about 2.0 to 6.0,u

and a more preferred range from 2.0 to 4.0M.`

The intervening layers may vary over an even wider range, however, apractical range may vary from 1.5 to 4.0pr.

The nature of representative elements and processes of the inventionwill be more readily understood by a consideration of the accompanyingdrawings in which,

Fig. 1 is a diagrammatical cross section of a lm element for singlecolor photographs and color component records.

Fig. 2 is a diagrammatic cross-section of a modied film element forsingle color photographs and color component records.

Fig. 3 is a diagrammatic cross-section of a modified lm element forsingle color photographs and color component records having an isolatinglayer. Fig. 4 is a diagrammatic cross-section of a lm element for singlecolor photographs having a nlm forming dye intermediate layer.

Fig. 5 is a diagrammatic cross-section of a modied film element having afilm forming dye intermediate layer.

Fig. 6 is a diagrammaticcross-section of a film element for 2colorphotography.

Fig. 7 is a diagrammatic cross-section of a modified film element for2color photography.

Fig. 8 is a diagrammatic cross-section of a further modied film elementfor 2color photography, bearing a non-halation layer.

Fig. 9 is a diagrammatic cross-.section of a film element for 3-colorphotography.

Fig. l0 is a diagrammatic cross-section of a modified nlm for 3-colorphotography. Fig. 11 is a diagrammatic cross-section of a modied filmfor 3-color photography.

The invention shall now be further illustrated, but is not intended tobe limited by the following examples:

EXAMPLE 1 p-Amino-N-diethylanlline hydrochloride grams-- 4 Sodiumsulflte (anhydrous) do 3 Sodium carbonate do 25 Water to liter-- 1 Thesilver and residual silver salt are then removed by means o'f Farmersreducer. A bluegreen dye image of good strength and color is formed. Across-section upon inspection under a microscope reveals that no coloris present in the light sensitive layer.

EXAMPLE 2 A iilm element as shown in Fig. 1 was prepared by coating thelm base with a gelatin dispersion of 1 part of salicylaldehydephthalaldehydic acid acetal of polyvinyl alcohol dispersed in about 5.3parts of gelatin to a thickness of about 5.0. Next was coated anunsensitized silver bromide-iodide emulsion layer about 2.0; thick.

The film element was exposed and developed in a solution prepared bymixing equal parts of the following solutions and further processed asin Example 1:

A. sodium sainte grams-- 2 p-Amino-N-diethylaniline do- 4 Metol 1 -do0.6 Water to liter 1 B. Sodium carbonate grams-- 40 Water to liter-- 1 vEXAMPLE 3 A film element identical with that set forth in Example 2except that a gelatin dispersion containing 1 part of1-(ln-stearoylaminophenylphenyl) -3-methyl-5-pyrazolone per 4 parts ofgelatin was used. 5

The element is exposed to an object and then treated as follows:

(a) Developed in a metol-hydroquinone developer of the followingformula:

Metol grams-- 1.4 Sodium sulfite, anhy do 60.0 Hydroquinone do 5.0Sodium carbonate, anhy do 48.() Potassium bromide do 1.5 Water to 1iter1 (b) Washed (c) Re-exposed to light (d) Developed in a mixture `ofequal parts of the following solutions to which was added aqueousammonium hydroxide (0.92 s. g.) equivalent to 2% by volume.

(e) The silver and residual silver halides were removed as in Ex. 1.

Exsmrta 4 A lm element (Fig. 1) comprising a gelatin subbed cellulosenitrate nlm base i is coated to form a layer 2 with a gelatin dispersioncontaining 1 part of l-(m-stearyphenyl) -3- methyl 5pyrazolone-o-benzaldehyde sulionic acid dimer to parts of gelatin to athicmss of about 4.0 u. A negative silver iodo-bro emulsion sensitizedwith thiopseudoey ethiodide is coated upon layer 2 to form a lightsensitive layer 3 about 2.5 p in thicmess. The nlm is then (l) exposedto an object, (2) developed 3 minutes lin a positive typemetol-hydroquinone developer, (3) washed without (4) re-exposed tolight, (5) developed in the following solution prepared Vby mixing equalparts of A and B:

Parts A. Sodium carbonate A Sodium snlte 1 Water 500 B.p-Amino-N-diethylaniline 2 Water 483 (6) The silver images and residualsilver halides are removed in a potassium ferricyanide hypo solution,then washed and dried. A magenta image sharp and uniform in color isformed solely in layer 2.

Examen: 5

p-Amino-N-diethylaniline grams-- 2 Ammonium hydroxide, conc cc-- Sodiumsulte, anhy l ;grams-- 2 Water to liter" 1 prepared by adding theammonia to a solution of the sodium sulite and then adding the developngagent. Water was then added to make one liter. The images are removedwith Farmers reducer. A blue-green image remained in layer 2.

EXAMPLE 6 A nlm element of the type set forth in Fig; 2 is prepared bycoating a thin layer of a. silver chlorobromide emulsion sensitized withthiopseudo cyanine ethiodide on a cellulose acetate nlm base, next athin layer of a gelatin dispersion containing 1 part of2-stearoylamino-5-naphthol-'-sulfonic acid per 7.5 parts of gelatin. Theelement is 1) Exposed to a blue-green object. (2) Developed in anordinary developer. 5 3) washed. V

(4) Developed without re-exposure in an aqueous bath of the followingcomposition:

A blue-green image oi good strength which is m sharp and uniform incolor results.

Examens 7 A nlm element (Fig. 3) comprising a cellulose nitrate base Ibearing a color-forming layer 2 prepared by coating thereon a gelatindispersion oi' 1 part of salicyladelhyde phthalaldehyliic acid acetal ofpolyvinyl alcohol dispersed in about 5.3 parts of gelatin to a thicknessoi' 5.0 p. A clear gelatin layer 4 is then coated on layer 2 to athickness of about 2.0 7.. Next is coated a positive type silveriodobromide gelatin emulsion to a thickness of about 4.0 p.

s The :dim element is exposed and processed after the manner set forthin Example 1, except 3g that a developer solution prepared by vmixingequal parte of A and B was used:

A. Sodium sulite -grams-- 2 p-Amlno-N-diethylaniline do 4 Metal dn 0.6

Water in liter-.. 1

B. Sodium carbonate grams-- 40 Water to 11m- 1 40 whereupon a blue-greenimage is formed. It is of good strength, uniform in color andmicroscopic examination shows the dye remains in the Vlayer next to thebase.

EXAMPLE 8 4.5

. Metol xrams-- 1.4 Sodium sulte, anhy ..do 60.0 Hydroquinone do- 5.0Sodium carbonate, anhy do 48.0

Potassium bromide do 1.5 Water to Hrm- 1 (b) Washed (c) Re-exposed tolight (d) Developed in a mixture oi equal parts of the followingsolutions to which was added aquecus ammonium hydroxide (0.92 0 s. g.)equivalent to 2% by volume.

m A. Sodium sulilte -grams 2 p-Amino-N-diethylaniline do 4 Metol dn 0.6Water to llter 1.0

B. Sodium carbonate grams-- 40 u Water to liter 1 (e) Bleached in analkaline potassium ferrocyanidel solution (f) Fi'xed in plain, 25% hypo,then washed and dried. c

A reverse magenta colored dye image is formed. It is of good strengthand color and sharp in detail. A microscopic examination reveals thatthe dye image remains wholly within layer 2. No color is formed inlayers 4 or 3.

A film base, e. g. subbed nylon, is coated with anequep-Aminodiethylaniline grams 2 Hexamethylene diamine (54% 'solution)cc 15 Sodium Asulilte grams-- 3 Water to -liter-- 1 (4) Washed andbleached in an alkaline potassium ferricyanide solution.

(5) Fixed in plain 25% hypo solution. (6) Washed and dried. A yellowimage is formed solely in layer 2. It is uniform in color, sharp indetail and of good strength. EXAMPLE 10 A cellulose nitrate film base I(Fig. 4) is coated with a color former having film formingcharacteristics from a 2% solution of 3,5-dichlor-`-salicylaldehyde-orthobenzaldehyde sulfonic acid acetal of polyvinylalcohol in 1 part of dimethyl i formamide, 3 parts ethyl alcohol and 1part water, which is made neutral by adding a small amount of causticsoda, to form a layer 2 about 1.() to 1.5 a thick. Next is coated alayer of a silver bromide emulsion about 4,- a thick.

The element is exposed to an image developed in a color formingdeveloper of the following composition p-Amino-N-diethyl anilinehydrochloride -grams..- 4 Sodium sulilte ....do 3 Sodium carbonate do 25Water to liter-- l Y The silver and silver salt are removed by a silversolvent which does not lattack color images. Suitable solvents includeFarmers reducer, a solution of potassium ferricyanide, and potassiumbromide followed by sodium thiosulfate.

A green dye image remains which upon micrcscopic examination is found tobe solely in layer 2'.

EXAMPLE 11 A film element (Fig. is made by coating a cellulose nitratebase i with a silver halide emulsion 3 after the .manner set forth inExample 2.

Upon this layer is coated a layer 2' after the manner set forth inExample with the same color former.

The lm is exposed to light and then processed as follows:

(a) Developed in an ordinary developer such as a glycin sodium carbonatedeveloper.

. (b) Washed and dried. y

(0)( Developed without re-exposure in a solution of the followingcomposition:

4,4diaminodiphenyl amine ..-grams 4 Hexamethylenediamine do 10 Sodiumsulflte do 2 Water to mar" 1 (d) Washed.

(e) kThe silver images are removed with a potassium ferricyanide-hyposolution.

A 'green dye image of good strength and color is formed solely in thelayer 2'.

EXAMPLE 12 A lm element'of the type set forth in Example 10 was made bysubstituting for the color former coating solution thereof a solution ofsymmetrical bls(m(5keto3pyrazyl)phenyl) .urea-formaldehyde resin in analcohol water solution (equal proportions containing 0.1 `part of NaOHper part of resin).

The resulting film element was exposed to light.

(1) Developed 3 minutes in a positive type Metol-h`ydroquinonedeveloper.

(2) Washed and dried.

(3) Re-exposed to light.

(4) Developed in the following solu on prepared by mixing equal parts ofA and Parts A. Sodium carbonate Sodium sulte 1 Water 500 B.p-Amino-N-diethylaniline 2 Water 483 (5) The silver images are removedin a potassium ferricyanide hypo solution, then washed and dried.

A magenta dye image which was sharp and clear in detail and uniform instrength and color was formed in layer 2 only.

EXAMPLE 13 A lm element having a cellulose acetate base was made in themanner described in Example 10 but a coating solution comprising 1 partof salicylaldehyde-phthaldehydric acid acetal of polyvinyl acetal(sodium salt solution) and 2 parts of polymethacrylamide dissolved inequal parts of water and alcohol was used.

It is then exposed and developed after the manner set forth in Example12 whereupon a blue-green dye image is obtained.

EXAMPLE 14 A two color print film as shown in Fig. 6 is made as follows:A cellulose nitrate lm base I is coated on one side with a gelatindispersion of one part of a mixture of yellow and magenta immobile colorformers per 4 parts of gelatin. The vmixture comprisesdiacetoacet-tolidine sulfone-o-benzaldehyde sulfonic acid dimer, 1 part,and 8 parts of l-(m-stearylaminophenyl)-3- methyl 5 pyrazolone-orthosulfobenzaldehyde dimer, 8 parts to form a layer 2 about 4.0 p. in

thickness. A layer 2 is coated on the other side lof the base from agelatin dispersion comprising 1 part of l-octadecyl amino--naphthol and6 parts of gelatin to a thickness of about 4.0 a. A lightsensitivegelatino silver iodo-bromide emulsion containing a4sens'itizing dye is coated on each oflayers 2 and 2' to form layers 3and 3' respectively.

I'he nlm element is then exposed by printing from bipack separationnegatives by white or colored light onto the emulsion layers. On layer 3there is imposed a latent image by printing with a blue light from thefront negative of a bipack.

On layer 3' by printing in a similar manner there is imposed a latentimagefrom the rear film (orange red record) of the bipack. Suitableprinting procedures and apparatus for the printing of the just-describedfilm are set forth in Brewster U. S. Patent 1,253,137.

The nlm is then processed as follows:

(a) Developed in a solution of the following composition: Ip-Amino-N-dietylamnne hydrocmonaag; 24 Sodium suliite (anhydrous) g-- 13 Sodium. carbonate--- ..1 g 20 Metol g-- 2 Water to- -liter-- l (b)Washed. v

. EXAMPLE A lm element of the type shownin Fig. 7 is prepared by coatinga gelatin solution containing a yellow screening dye on one side of acel- 'lulose nitrate base to form a thin layer 6. Over the yellow layeris coated a gelatin dispersion per 4 parts of gelatin. The color formermixture comprises N-Ndi(acetoacet)-m-tolidine-6,6'-sulfone-benzaldehyde-o-sulfonic acid dimer,

1 part, and 8 parts of l-(m-stearoylaminophenyl) 3-methyl-5-pyrazolone-benzaldehydeo-sulfonic acid dimer and the layer iscoated to about 4 a in thickness. O ver this is coated a layercomprising a blue light sensitive gelantinesilver iodobromide emulsionof about 5 u thickness. On the opposite side of the base is coated ablue light sensitive gelatin-silver iodobromide emulsion coated to athickness of 5 n. Next is coated a thin layer from a dispersion whichconsists of 1 part blue-green color former salicylaldehydeortho sulfobenzaldehydeV mixed acetal of polyvinyl alcohol (sodiumfsalt solution)dispersed in 3 parts of gelatin and coated to a thickness of about 4 u.

A similar element which has considerable utility can be made by mixingthe comminute silver with the mixture of immobile yellow and magentacolor formers and gelatin to form a single layer. Similar duplicoatedfilm elements can be made 'by mixing comminute silver with a singlecolor former.

The exposed nlm elements of Examples 15 and |5A are then treated asfollows:

(a) Developed 10 minutes in a solution prepared by mixingequal parts ofthe following of one part of a mixture of yellow and magenta immobilecolor formers per 4 parts of gelatin. The mixture comprisesdiacetoacet-tolidine sulfone-o-benzaldehyde sulfonic acid dimer. l part,and 8 parts of l-(m-stearoylaminophenyl)-3- methyl-5-pyrazolone orthosulfobenzaldehyde dimer to form a layer 2 about 4.0 u in thickness. Alayer 2' is coated on the other side of the base from a gelatindispersion comprising l part of l-octadecylamino--naphthol and 6 partsof gelatin to a thickness of about 4.0 n.

A light sensitive gelatino silver bromide emulsion is coated on each oflayers 2 and 2' to form layers 3 and 3 respectively.

Color separation negatives from a two colorv bipack .are printed on tothe above-described film element as follows:

On layer 3 there is imposed a latent image by printing with a blue lightfrom the front negative (blue-green record) of a bipack on 3 from therear negative.

The exposed film element is processed to color after the manner setforth in Example 14.

EXAMPLE 15-A A film element of the general type shown in Fig. '1 isprepared by coating a gelatin dispersion of comminute silver particleson one side of a cellulose nitrate base, forming a thin layer with aneutral absorption density of 1 to 3, (as measured on a Martensphotometer). Over this is coated a gelatin dispersion of 1 part of amixture of immobile yellow and magenta c0101' .formers 1 Parts A. Sodiumcarbonate 20 Sodium sulflte 1 Water 500 B.- p-Amino-N-diethylaniline 2Water 483 (b) washed.

(c) 'I'he silver images and residual silver salts are removed bytreatment with alkaline fen-icyanide solution followed by xing in plain25% aqueous sodium thiosulfate solution.

A colored transparency which reproduces the original scene is obtained.The dye images are clear and sharp in detail with no dilution of color.A microscopic section shows the dye images to be in a single strata.

EXAMPLE 16 A film element as shown in Fig. 8 is made by coating acellulose nitrate lm base I with a red sensitive high contrastgelatino-silver bromide emulsion sensitized with 20 mg. per kg. ofemulsion, of 3,3'diethyl9-methyl thiocarbocyanine iodide to a thicknessof about 4.011.. Upon this layer is coated a gelatin dispersion of 1part of the yellow color former N-furoylacetN-benzoyl acetbenzidide per4 parts of gelatin to form a thin layer 1. On this layer is coated agelatin dispersion of l part of the magenta color former l-(m-stearoyl-amino phenyl) 3methyl5pyrazo lone and 4 parts of gelatin toform a thin layer 3. A blue sensitive gelatin silver bromide emulsioncontaining a soluble yellow screening dye, e. g. tartrazine is coated onlayer 8 to form a thin light sensitive layer 9. On the reverse side ofthe base is coated a gelatin dispersion containing the blue-green 'colorformer salicylaldehyde-o-benzaldehyde sulfonic acid acetal of polyvinylalcohol, 'l part per 4 parts of gelatin to form a thin layer I0. Uponlayer I 0 is coated a photographic emulsion containing a yellow lter dyeof the Salime type used for layer 9 to form a thin layer i i :l'he lmelement may be exposed to printing light from color separation negativesas described in Example 14, and then processed as follows:

(l) Developed 10 minutes in a bath of the' following composition made bymixing equal parts of A. Sodium sulfite grams-- p-Amino-N-diethylaniline--do- Water to iiter-- B. Sodium carbonate -grams-- 4 Water to liter--(2) Bleached 7 minutes in a solution containing 3V: by weight ofpotassium ferricyanide and ExAMPLE 17 A film element as shown in Fig. 9is prepared as follows. An aqueous gelatin dispersion containing 2% ofthe sodium salt of salicylaldehydeo-sulfobenzaldehyde mixed acetal withpolyvinyl alcohol, and 4.5% of gelatin by weight, is coated on celluloseacetate film base I to form a thin layer I2. A red sensitive,green-blind silver iodobromide gelatin emulsion containing 18 mgs. perkg. of emulsion of 3-ethyl-a-naphthselenocarbo cyanine-3'-ethio'dide iscoated on layer I2 to form a light sensitive layer I3. A plain gelatinlayer Il is coated on layer I3 and next an aqueous gelatin dispersioncontaining 1%r of the magenta color former 1-(m-stearoylamino-phenyD-3-methyl-5-pyrazolone to form a thin layer I5. Upon this layer is coated alight sensitive layer I6 comprising an orthochromatic negative gelatinsilver chloride emulsion containing 3,1'-diethyl-5-methyl-6methoxy benzthio-Z'- cyanine iodide. Next is 'coated a blue light screening layerI'lv from a 2% aqueous gelatin dispersion of 0.3%- by weight4-piperonylbutadlenyl-a-pyridinium stearyl bromide. On layer I1 iscoated a thin yellow color forming layer I8 from an aqueous solution ofgelatin containing 3.5% of gelatin and 1% ofdi(acetoacet)metatolidine6,6' sulfone. A blue sensitive gelatine-silverbromide emulsion is then coated to form a thin outer layer 15 minutes ina dye-generating reducer of the following formula:

Sodium suliite, anhydrous K gram 1.0 p-Aminodiethyl anilinedihydrochloride do- 2.0 Hexamethylene diamine (40%) solution cc-- 20Water to -liter-- 1 4. Wash 10 minutes. 5. Bleach 7 minutes in asolution containing HO HAN 3%% by weight of potassium ferricyanide andmade alkaline with ammonium hydroxide or sodium carbonate.

6. Rinse.

7. Remove bleached silver in a 25% solution oi' hypo (crystalline sodiumthiosulfate).

8. Wash 15 minutes and dry.

` I'he color photograph resulting from the above process is ofexceptional clarity and brilliancy. The saturation of dyes or dyedensities is considerably greater than that obtained by known methods ofprocessing. A modified illm may be made by incorporating comminutesilver in the color former layer by preparing comminute silver particlesand incorporating them in the gelatin dispersion, which forms the bottomcolor former layer. Microscopic examination shows that the color imagesremain solely in the layers in which the color formers were originallyplaced.

ExAMPLr.' 18

A film element as shown in Figure l0 was prepared in the same manner asExample 17 except that the red sensitive emulsion layer and bluegreencolor former layers were reversed. This element comprises a cellulosenitrate base I, a red-sensitive silver halide emulsion layer I3, next ablue-green color former layer I2, next layers I4, I5, I8, I1, I8 and I9identical with those of Example 1-7. A water soluble antihalation layer2U was coated on the reverse side of base I.

The film was exposed to an original color scene and processed after themanner set forth in Example 16..

A modied film may be made by first coating a comminute silver layer onone side of the base to serve asv an antihalation layer. The remaininglm is made as above by superposing the layers on the antihalation layer.

pared after the manner set forth in Example 1'1 using the same colorformers. This element eliminates gelatin separating layer between thebluegreen and magenta color forming layers. It comprises a celluloseacetate base I, a red sensitive silver halide emulsion layer I3, ablue-green color former layer I2, a magenta color former layer I5, anorthochromatic silver halide emulsion layer I6, a magenta color formerlayer I5' containing a yellow screening dyez a yellow color former layerI8 and a blue sensitive silver halide layer I9. A non-halation layer 20is coated on the reverse side.

This film is exposed and developed to dye images after the manner setforth in Example 17.

EXAMPLE 20 A lm element of the type set forth in Example 16 is preparedin the same manner, but the following color formers were used in placeof those described in that example.

Blue-green 3-a1lyl salicylaldehyde-ortho sulfo benzaldehyde mixed acetalof polyvinyl alcohol. One part of this is dispersed in 3 parts gelatin.

This nlm was exposed with white light through a positive colortransparency with white light or with appropriately colored lightthrough separation positive films or to an original color scene and thendeveloped in the following solution:

Parts A. Sodium carbonate 20 Sodium sulilte .1

Water 500 Parts B. p-phenylenediamne `hydrochloride v2 Water 483 Mixequal parts of A and B.

After development (the developing solution of Example I may also lbeused), and washing, the nim is placed in a diazo solution prepared asfollows: 6.1 parts of dia'nisidine is dissolved in 125 parts of boiling1 molar hydrochloric acid and4 cooled to 2-4 C., then 10 parts of 5molar sodium nitrite solution is added at 24 C. After 5 minutes, themixture is filtered land diluted with ice water to 4000 parts. After thelm has been immersed in this solution for 30 seconds, it is removed andimmediately placed in a solution containing 3 per cent by weight ofammonia which has been cooled to C. After remaining in this solution.for 30 seconds, it is removed and thoroughly washed. The nlm is nextplaced in a solution prepared by dissolving first parts of coppersulfate in 90 parts of water and then adding 5 parts of potassiumbromide and 5 parts of concentrated hydrochloric acid. When the silverimage has been completely oxidized the film is-removed, washed and xed.The resulting film contains a full color positive in azo dyes.

Film elements of the structure set forth in Fig. 1 to ll inclusive whichcontain color formers capable of forming quinoneimine or azomethine dyesand azo dyes may be processed in a'similar manner to that set forth inExample 20. Suitable procedures are also set forth in Woodwardapplication, Serial No. 335,416, led May 15, 1940, now U. S. P.2,297,732.

In the embodiment of the invention wherein no re-exposure to light isused, the dye forming solutions set forth in Meschter application,Serial No. 295,686, now U. S. P. 2,310,981, may be used with similarresults.

In place of the specific immobile color formers set forth in thepreceding examples may be substituted a large number-of exceedinglydiverse color formers. The types which are to be dispersed in gelatin orother similar colloid binding agents may be (1) substantive to thegelatin or binding agent, (2) soluble in aqueous alkaline liquids butfast to diffusion when present in emulsion layers, (3) colloidal innature so that they cannot be extracted by simple extraction-from thelayer, (4) high molecular weight so that migration through Athe cellularstructure of the binding agent is prevented, (5) highly insoluble, (6)lm-forming. Substantivity can be strengthened by agents which haveprecipitating action, ei; g. diphenyl guanidide, diphenyl biguanidide, ec. A

The immobile dye intermediates or color formers in general contain 'twocomponents, (l) a color forming dye coupling component or nucleus and acomponent group or nucleus which increases the molecular weight so thatthey become immobile in the water permeable colloid layers or (2) groupsforimparting substantive character (which are of the same type as usedin makor structures which make it colloidal in character.

' Suitable dyestuif components for color-forming development and azoreversal processes hereof which fall within one or more of the abovetypes of immobile color formers include:

l. Higher aliphatic and cycloallphatic derivatives of dye intermediateswherein the aliphatic radical such as an alkyl, alkoxy or long chaincarboxylic acid acyl radicals contain a carbon chain of more than 8carbon atoms and preferably at least 12 carbon atoms, such compoundsincluding active methylene compounds such as aroylor acylacetanilides,phenylmethylpyrazoiones, etc., higher aliphatic amides of phenoliccompounds, and alphaand beta-naphthols which preferably contain somesolubilizing group such as carboxyl or sulfonic, which are characterizedin that they have a reactive position capable of entering the couplingreactants but not necessarily an unoccupied position ortho or para tothe phenolic hydroxyl group. Suitable compounds of the cycloaliphatictype are set forth in U. S. Patent 2,189,817.

2. Polyvinyl -acetals of aromatic aldehydes which are capable ofreacting with diazo compounds and the oxidation products of photographiccolor developers. The acetals are formed from polyvinyl alcohol orpartially hydrolyzed polyvinyl esters and aromatic aldehydes whichcontain a phenolic hydroxyl, amino, alkyl, cycloa1ky1-, oraryl-substituted amino group including mixed groups of this type, whichare further characterized in that they have a reactive position, but notnecessarily unoccupied position, ortho or para to the mentioned groupsor the aromatic aldehydes having an active meth'ylene group. Thepreparation of suitable compounds of this type is set forth in Dorough8i McQueen application, Serial No. 233,480, filed October 5,

' 1938, now U. S. P. 2,310,943.

3. Condensation products of phenols and naphthols or hydroxy aromaticcarboxylic or sulfonic acids with difunctional resin forming reagentssuch as aldehydes and ketones, dimethylol derivatives of phenols, amidesand amines and equivalent compounds. The preparation of suitable colorformers of this type is described in McQueen application, Serial No.261,794, filed March 14, 1939 now U. S. P, 2,323,481.

4. Condensation products of amine-containing dye intermediates such asaminophenols, aminonaphthols, N-aminoalkylor aminoaryl-aminonaphthols,amine containing Y active methylene compounds such as amino aroyloracetylacetanilids, amino-phenylmethylpyrazolones or any of the precedingcompounds containing solubilizing groups such as carbonyl or sulfonic,with polycarboxylic acids and their derivatives such as the anhydrides,esters, amides or halides. Such polymeric acids include theolefin-maleic anhydride'interpolymers, polyacrylic acids andinterpolymers of esters of olen dicarboxylic acids with vinyl esters,olenns and styrene as described in U. S. Patent 1,945,307.

A5. Immobile dye intermediates formed from N-mono and dialkylated oraralkylated 1,5- and 1,8-aminonaphthols containing in a side chain agroup capable of further condensation such as amino, thio, carboxyl,formyl, etc.,'by condensing said compound with a suitable high molecularweight compound such as aliphatic acids or amines with more than 8carbon atoms or polymeriaclds or derivatives as Suitable immobile dyeintermediates of the above and other types which are useful for colordevelopment and azocoupling processes are disclosed in U. S. Patents2,154,918, 2,166,181, 2,178.-

612, 2,179,228, 2,179,238, 2,179,239, 2,179,244, 2,186,045, 2,186,719,2,186,734, 2,186,735, 2,186,736, 2,186,849, 2,140,540, 2,133,937,2,200,924, etc. and may be substituted for the dye intermediates of theabove examples in accordance with the .teachings hereof. j v

The preferred developing agents which may be used in the dye couplingdevelopment steps hereof are derivatives'of p-phenylenediamine andparticularly the asymmetric dialkyl p-phenylenediamines of 1 to 4 carbonatoms, e. g. p-aminodimethylanlline, p-aminodiethylanillne,p-aminodibutylaniline, etc. Other developing agents which may be usedinclude p-phenylenediamine itself, p-methylaminoaniline.p-ethyiaminoaniline, p-aminophenol, N,N-diethylo-phenylenedi amine,chloro-p-phenylenediamine, 1,2,5-toluylenediamine,2-amino-5-diethylaminotoluene, pamino-N-phenylmorpholine,N-p-aminophenylpiperidine, N-methyl-N-hydroxyethyl-p-phenylenediamine,N-butyl-N-hydroxyethyl-p-phenylenediamine,2-amino-5-(N-butyl-N-hydroxyethyl) aminotoluene,-'y-dihydroxypropyl-p-phenylenediamine, etc., These aromaticamino-developing agents in the form of their organic or accesso suitableamines are those containing halogen, alkoxy, nitro, carboxy, andsulfonic acid groups.

For successful operation of the azo reversal processes hereof, it isnecessary to have diazonium compounds that'will couple lwith threecolorless components to yield the three subtractive primary colors,yellow, magenta and blue-green.

VAlmost all diazotisable amines can be coupled with phenolic couplingcomponents and active methylene compounds such asphenylmethylpyrazolone, acetoacetanilide and aroyiacetanilides,v

zidine and diaminonaphthalene derivatives subinorganic acid'salts may beused in the preparation of the developing solutions. The salts are ingeneral more stable thanv the free bases. `As examples of suitablesalts, mention is made oi' the hydrochloride, sulfates, acetates, etc.

Further examples of developing -agents that can be used in this processare-heterocyclic compounds containing benzene nuclei such as 1,2,3,4-

tetrahydro-G-aminoquinoline, 1,2,3,4tetrahydro coupling `to azo dyes arewell known in the art (see Fierz-Davis Kunstliche Organische Farbstaffe"and J. C. Cain The Chemistry ofthe Diazo Compounds, pages 6-26). Thereare in general of the type RNHawhere R, is aromatic or a heterocyclicring such as pyridine, pyrazolone, etc. The R may also be substitutedwith various groups such as halogen, alkyl, alkoxy, aryl, sulfonic,carboxyl, etc. In choosing the amine to be lused there are in generaltwo considerations to be observed, (l) the diazo compound must besufliciently active to couple readily with the dye intermediate used ata relatively low temperature and in aqueous solution; (2) the diazocompound must be one which can be coupled to'yield bright azo dyes withspectral characteristics suitable for use in three-color photography,that is, they must have fairly denite and sharp absorption bands. Thus,the most' tiary, and must remain basic.

stituted with halogen, alkoxy, and sulfonic acid groups may also beused. In forming the bluegreen azo color, the choice is furtherrestricted since the best colorless coupling components which. adhere tothe previous qualications are derivatives of 1,5 and 1,8-aminonaphtholin which the amino. group is preferably secondary or ter- The preferreddiazotizable amines that can be used for forming all three colorstherefore are substituted benzidine derivatives containing halogen,alkyl, nitro, carboxyl, alkoxy or sulfonic acid groups, and substitutedpara-nitroaniline derivatives containing the 2 position halogen, alkoxy,nitro, carboxyl or sulfonic acid groups which all give desirableproperties to the diazo components and to the dyes.

The novel lm elements hereof are not limited in their use to theformation of azo dye images by the processes set forth above and inWood- Ward, Serial No. 335,416, now U. S. P. 2,297,732 but may beprocessed in other manners as described below.

'I'he novel iilm elements hereof may be `color developed and azo coupledafter the manner set forth in British Patent 503,824 which involves aneliminationof the quinoneimine or azomethine images by bleaching, ifnecessary.

The elements may also be exposed, bleached to a silver salt image suchas a silver ferrocyanide which are then reduced with an aromatichydrazine, and subsequently the silver and silver salts are removed. Thedye intermediate in this case acts as an azo coupling component whichcouples with the` development products of the hydrazine to form azodyes. Suitable dye intermediates and processes are described in Woodwardand McQueen application, Serial No. 299,760, filed October 16, 1939.

While gelatin has been described as the binding or supporting agent inthe majority of the examples, the invention is not hunted to theuse ofthis material. On the contrary, a large number of materials some ofwhich are readily available can be substituted in similar amounts andcoatedin the above manners. Natural and synthetic materials such asgums, resins, cellulose derivatives, carbohydrate derivatives. etc. The-materials in general must be substantially water insoluble but waterpermeable.

Suitable specific materials include polyvinyl and polybasic acids, e. g.phthalic, maleic, succinic, etc. Higher fatty acids, e. g. stearic,palmitic. and oils such as castor oil, may be used as modifying agents.The alkyd resins delscribed in McQueen application, Serial No. 276,718,iiled May 31, 1939, now U. S.v P. 2,290,289, may be used.

Condensation products of phenols, of naphthols, or of hydroxy aromaticcarboxylic or sulfonic acids with bifunctlonal resin-forming reagents,for example, aldehydes and ketones, dimethylol derivatives of phenols,of amides, or oi' amines, and oi' equivalent compounds, may be used.

Condensation products of amine-containing dye intermediates, withpolycarboxylic acids or with their derivatives such as the anhydrides,esters, halides, or amides may be used. Polymeric acids of this type andtheir derivatives include the polyvinyl ethers of hydroxy acids,oleiin-maleic anhydride interpolymers, polyacrylic acid, polymericolefin discarboxylic esters and interpolymers of esters of olefindicarboxylic acids with vinyl esters and `styrene as described in U. S.Patent 1,945,307.

The above and equivalent materials as previously indicated can be usedas bindingagents i'or the color yielding layers as well as the silvervsalt layers or intervening layers in each of the herein describedconstructions of lm elements.

While only a few types of iilm constructions have been set forth aboveand illustrated in the drawings, it should be understood that theinventlon is not limited to those modifications.. Thus, a iilm formingtype of color former may be imposed directly on a base which may besubbed, next an intervening water permeable layerl and ilnally areducible silver salt layer, or these layers may be reversed. Similararrangements can be made with the dye intermediates incorporated in awater permeable binder or support. If a plurality of color yieldingunits are embodied in a lm element one or more of the color yieldinglayers may be composed of lm forming dye `intermediates and the other orothers may be composed of dye intermediates dispersed ,in bindingmediums which are water permeable.

In the case of monopacks, various arrangements as indicated above may bemade. The layers may be arranged so that exposure is made through thebase. Thus, the elements shown in Figs. 9, 10 and 1l, may be reversedwith the base on top instead of the bottom. This requires a reversal ofcoating steps.

Not only may monopacks be fabricated, but biand tri-packs embodying theabove constructions may be made ,without departing from the spirit andscope of the invention. n

While cellulose derivatives have been described in the majority of theexamples, various other types of transparent, translucent as well asopaque supports may be used. Synthetic resins including acrylic andhydrocarbon substituted acrylic. acid resins, meta-styrene resins, vinylresins. e. g. vinyl chloride acetal, polyvinyl acetals,

synthetic linear polyamides, glass, paper and many other materials maybe used.`

An important aspect of this invention is briefly illustrated in Example-A, and involves the use of comminute silver in an immobile dyeintermediate layer oi' an element used for multicolor photography. Thisembodiment may be used in films which contain at least one coloryielding unit on each side of a transparent base. However, the elementsmust be so constructed that a combined comminute silver color yieldinglayer is between two reducible silver salt layers. This arrangement isadvantageous in that it prevents a printing light from ailecting one ormore other sensitive layers. The above arrangements are oi particularimportance in duplicoats. It not only saves one coating step butproduces in Vcertain cases a superior product than if light screeningdyes are used.

Various types of reducible silver salts may be used in the lightsensitive layers'. Initially they are generally silver halide layerssuch as simple and mixed chloride, bromide and iodide emulsions,including sliver bromide, silver chloride, silver chloride-bromide,silver bromide-iodide, silver iodide. etc. or the type used in the moreconventional lm elements used for color forming development. 'I'hey maycontain the usual emulsion components such as desensitizing dyes,sensitizing dyes, e. g. cyanine, carbocyanine, pseudocyanine,merocyanine, cyazine, carbocyazine, etc. salts and bases; etc. Theselight sensitive emulsions after development to silver images may bebleached in the usual manner to form silver ferrocyanide images beforecolor development or color formation.

The particular types of coating solutions used can be made up and coatedin a manner similar to those which have been used in the manufacture oflm elements containing immobile dye intermediates in emulsion layers.The immobile dye intermediates may be dispersed in the binding agentswhile in a-inely divided state using dispersing agents if desired and/oralkalies. In 45 many cases it is practical to dissolve the dyeintermediate or color former in a 5 to 10% caustic alkali to form asoluble paste. This may be then diluted with about 5 parts oi water andabout 1 part of alcohol added to 5% aqueous gelatin and the excessalkali neutralized with a mineral acid such as hydrochloric. The usualphotographic coating ingredients, Spreading agents, e. g. glycerine,saponine, long chain alkyl sulfates, etc. may be employed. Theconcentration of the coating solution is adjusted to yield the desiredthickness.

The usual types of subbing solutions may be used for anchoring thesilver halide emulsion layersl to the base and to adjacent color formeror intervening layers. The usual emulsion subbing solutions may also beemployed toanchor the dye intermediate or color former layers toadjacent layers which may be emulsion layers or intervening layers.

This invention has a number of advantages, an important one being thatthe natural sensitivity and articial sensitization of the silver halideemulsion layers is not impaired'. Many color formers which are readilyavailable and form excellent quinoneimine, azomethne and azo dyes have avery deleterious effect on the speed of photographic emulsions and forthis reason cannot be used. In many cases the contrast of the iilm isexcessively depressed. However, such color formersbecome of` value whenused in accordance 75 with the teachings of this invention.

assoso Another important advantage resides in the improved stability ofthe resulting nlm elements. The methods employed for incorporating colorformers in emulsions often lead to unstable films. When dispersionismade before contact is made with the sensitive layerl this defect iseliminated. Furthermore, some color formers give rise to fog because oftheir chemical structure, but may be safely employed by this invention.

A further advantage resides in the fact that a wider selection ofoptical sensitizers is permitted. Many of the most powerful sensitizersfor the red and green regions may not be employed in emulsionscontaining color farmerssensitization to the longer wave lengths beingpartially or completely destroyedby the color former. Thisincompatibility is avoided by placing the color formers in adjacentlayers.

The invention also provides the following production advantages:

(a) Color former dispersions may be prepared in advance of the coatingschedule. They may be standardized for degree of dispersion, colloidalstability, and color forming strength. All these operations may becarried out in white light areas; darkroom conditions being unnecessaryprior to the coating operation.

(b) IIhe consumption of costly materials is reduced since the colloidaldlspersions are relatively stable, thus permitting them to be reworkedby re-melting the chilled and jelled dye-forming colloid. On the otherhand, previous research has shown that the photographic stability oflight sensitive emulsioncolor former preparations is short-lived md theuncoated preparations deteriorate rapidly even under refrigeratedstorage conditions.

As many apparently widely different embodiments of this invention may bemade without departing from the spirit and scope hereof it ls to beunderstood that I do not limit myself to the specific embodiments hereinexcept as defined by the appended claims.

I claim:

l. A photographic element comprising a transparent hase havingsuperimposed on one side thereof in order a red sensitive silver halideemulsion layer, a gelatin layer containing an immobile blue green colorformer, a gelatin layer containing an immobile magenta color former, agreen sensitive silver halide emulsion layer, a gelatin layer containingan immobile magenta color former and a yellow light screening dye, agelatin layer containing an immobile yellow color former and a bluesensitive silver halide emulsion layer.

2. A photographic element comprising in the following order a redsensitive silver halide emulsion layer, a gelatin layer containing animmobile blue green color former, a gelatin layer Containing an immobilemagenta color former, a green sensitive silver halide emulsion layer, agelatin layer containing an immobile magenta color former, a gelatinlayer containing an immobile yellow color-former, a blue sensitivesilver halide emulsion layer and a stratum containing at yellow filterdye interposed before the green sensitive and red sensitive silverhalide layers and a transparent base on one side of said element.

3. A photographic element comprising a transparent base havingsuperimposed on one side thereof in order a red sensitive silver halideemulsion layer, a gelatin layer containing an immobile blue green colorformer, a gelatin layer containing an immobile magenta color formen'agreen sensitive silver halide emulsion layer, a gelatin layer containingan immobile magenta color former and a yellow light screening dye, agelatin layerV containing an immobile yellow color former and a bluesensitive silver halide emulsion layer and a non-halation layer on theother side.

4. A photographic element having a plurality of layers in the followingorder: a red sensitive silver halide emulsion layer, a gelatin layercontaining the sodium salt of salicylaldehyde-o-sulfobenzaldehyde mixedacetal of polyvinyl alcohol, a gelatin layer containingl-(m-stearoylaminophenyl) -S-methyl-5-pyrazolone-benzaldehyde-osulfonicacid dimer, a green sensitive silver halide emulsion layer, a gelatinlayer containing l-(mstearoylamincphenyD-Smethyl--pyrazolonebenzaldehyde-o-sulfonic acid dimer, a gelatin layercontaining N-furoylacet-N'-benzoylacetobenzidide, a blue sensitivesilver halide emulsion layer. a stratum containing a yellow filter dyeinterposed before the green sensitive and red sensitive silver halidelayers, and a transparent base on one side of said layers.

5. A photographic element having a plurality of layers in the followingorder: a red sensitive silver halide emulsion layer, a gelatin layercontaining an ethylene maleic anhydride-l-pamino-benzy1amino-5-naphtholpolymer, a gelatin layer containing 2-stearoy1amino-5-naphthol-Z-sulfonic acid, a green sensitive silver halide emulsion layer, agelatin layer containing 2- stearoylamino-5-naphthole'l-sulfonic acid, agelatin layer containing 3-allyl-salicylaldehyde-o sulfobenzaldehydemixed acetal of polyvinyl alcohol, a blue sensitive silver halideemulsion layer, a stratum containing a yellow lten dye interposed beforethe green sensitive and red sensitive silver halide layers, and atransparent base on one side of said layers.

6. A photographic element having a plurality of layers in the followingorder: a red sensitive silver halide emulsion layer', a gelatin layercontaining m-octodecyloxyphenol, a gelatin layer containing 1-(rn-stearoylaminophen'yl) -3meth yl-5pyrazolone-benzaldehyde o sulfonicacid dimer, a green sensitive silver halide emulsion layer, a gelatinlayer containing l-(m-stearoylaminophenyl) -3-methyl- 5-pyrazolone-benzaldedye-o-sulfonic acid dimer, a gelatin layercontaining di(acetoacet)-metato1idine-6,6'sulfone, a blue sensitivesilver halide emulsion layer, a stratum containing a yellow filter dyeinterposed before the green sensitive and red sensitive silver halidelayers, and a transparent base on one side of said layers.

CLAYTON F. A. WHITE.

CERTIFICATE OF CORRECTION. 1 'Patent No. 2,559,580. June 6, 19141;.

' CLAYTON F. A. WHITE.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 8,second column, line 55, strike out the number and period "M SJ; page 9,second column, Aline 19, for components read -co mponents; page 11,second column, lines 5'? and 58, claim 6, for "benzaldedye" read-b'enzaldehyde; and that the said Letters Patent shouldbe read with'this correction therein that the same may conform to the record of thecase in the Patent Office.

Signed and sealed this 8th day of August, A. D. 19141;..

Leslie Frazer (Seal) Acting Commissioner of Patents.

